开始尝试从0写一个项目--后端(一)

创建文件的目录结构

利用这个界面创建

|--------|-------------|--------------------------------------------|
| 序号 | 名称 | 说明 |
| 1 | SEMS | maven父工程,统一管理依赖版本,聚合其他子模块 |
| 2 | sems-common | 子模块,存放公共类,例如:工具类、常量类、异常类等 |
| 3 | sems-pojo | 子模块,存放实体类、VO、DTO等 |
| 4 | sems-server | 子模块,后端服务,存放配置文件、Controller、Service、Mapper等 |

配置pom文件

文件路径:SEMS\pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.3</version>
    </parent>
    <groupId>com.ljc</groupId>
    <artifactId>SEMS</artifactId>
    <packaging>pom</packaging>
    <version>0.0.1-SNAPSHOT</version>
    <modules>
        <module>sems-common</module>
        <module>sems-pojo</module>
        <module>sems-server</module>
    </modules>

    <!--它定义了一系列项目依赖的版本号-->
    <properties>
        <mybatis.spring>2.2.0</mybatis.spring>
        <lombok>1.18.20</lombok>
        <fastjson>1.2.76</fastjson>
        <commons.lang>2.6</commons.lang>
        <druid>1.2.1</druid>
        <pagehelper>1.3.0</pagehelper>
        <aliyun.sdk.oss>3.10.2</aliyun.sdk.oss>
        <knife4j>3.0.2</knife4j>
        <aspectj>1.9.4</aspectj>
        <jjwt>0.9.1</jjwt>
        <jaxb-api>2.3.1</jaxb-api>
        <poi>3.16</poi>
    </properties>

    <dependencyManagement>
        <dependencies>
            <!--mybatis的依赖-->
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>${mybatis.spring}</version>
            </dependency>

            <!--Lombok 是一个 Java 库,用于自动化生成如 getter、setter、toString 等方法-->
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <version>${lombok}</version>
            </dependency>

            <!--一个 Java 语言编写的高性能功能完善的 JSON 库-->
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>fastjson</artifactId>
                <version>${fastjson}</version>
            </dependency>

            <!--一个包含大量静态方法的库,用于处理 Java 核心 API 中没有的常用功能-->
            <dependency>
                <groupId>commons-lang</groupId>
                <artifactId>commons-lang</artifactId>
                <version>${commons.lang}</version>
            </dependency>

            <!--阿里巴巴开源的数据库连接池-->
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid-spring-boot-starter</artifactId>
                <version>${druid}</version>
            </dependency>

            <!--MyBatis 分页插件-->
            <dependency>
                <groupId>com.github.pagehelper</groupId>
                <artifactId>pagehelper-spring-boot-starter</artifactId>
                <version>${pagehelper}</version>
            </dependency>

            <!--Swagger 的增强 UI 实现,用于 API 文档生成-->
            <dependency>
                <groupId>com.github.xiaoymin</groupId>
                <artifactId>knife4j-spring-boot-starter</artifactId>
                <version>${knife4j}</version>
            </dependency>

            <!--AspectJ 是一个面向切面的编程(AOP)框架-->
            <dependency>
                <groupId>org.aspectj</groupId>
                <artifactId>aspectjrt</artifactId>
                <version>${aspectj}</version>
            </dependency>

            <dependency>
                <groupId>org.aspectj</groupId>
                <artifactId>aspectjweaver</artifactId>
                <version>${aspectj}</version>
            </dependency>

            <!--Java JWT(JSON Web Tokens)库,用于生成和解析 JWT 令牌-->
            <dependency>
                <groupId>io.jsonwebtoken</groupId>
                <artifactId>jjwt</artifactId>
                <version>${jjwt}</version>
            </dependency>

            <!--阿里云对象存储服务(OSS)的 Java SDK-->
            <dependency>
                <groupId>com.aliyun.oss</groupId>
                <artifactId>aliyun-sdk-oss</artifactId>
                <version>${aliyun.sdk.oss}</version>
            </dependency>

            <!--用于将 Java 类映射到 XML 表示-->
            <dependency>
                <groupId>javax.xml.bind</groupId>
                <artifactId>jaxb-api</artifactId>
                <version>${jaxb-api}</version>
            </dependency>

            <!-- poi -->
            <dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi</artifactId>
                <version>${poi}</version>
            </dependency>
            <dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi-ooxml</artifactId>
                <version>${poi}</version>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>

SEMS\sems-server\pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>com.ljc</groupId>
        <artifactId>SEMS</artifactId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>

    <artifactId>sems-server</artifactId>

    <dependencies>

        <dependency>
            <groupId>com.ljc</groupId>
            <artifactId>sems-common</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>

        <dependency>
            <groupId>com.ljc</groupId>
            <artifactId>sems-pojo</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <scope>compile</scope>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjrt</artifactId>
        </dependency>

        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
        </dependency>

        <dependency>
            <groupId>com.github.xiaoymin</groupId>
            <artifactId>knife4j-spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-cache</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-websocket</artifactId>
        </dependency>

        <dependency>
            <groupId>javax.xml.bind</groupId>
            <artifactId>jaxb-api</artifactId>
        </dependency>

        <!-- poi -->
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

SEMS\sems-pojo\pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>com.ljc</groupId>
        <artifactId>SEMS</artifactId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>

    <artifactId>sems-pojo</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.9.2</version>
        </dependency>
        <dependency>
            <groupId>com.github.xiaoymin</groupId>
            <artifactId>knife4j-spring-boot-starter</artifactId>
        </dependency>
    </dependencies>
</project>

SEMS\sems-common\pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>com.ljc</groupId>
        <artifactId>SEMS</artifactId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>

    <artifactId>sems-common</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
        </dependency>
        <dependency>
            <groupId>commons-lang</groupId>
            <artifactId>commons-lang</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-json</artifactId>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt</artifactId>
        </dependency>
        <!--支持配置属性类,yml文件中可以提示配置项-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>com.aliyun.oss</groupId>
            <artifactId>aliyun-sdk-oss</artifactId>
        </dependency>
        <dependency>
            <groupId>javax.xml.bind</groupId>
            <artifactId>jaxb-api</artifactId>
        </dependency>
        <!--微信支付-->
        <dependency>
            <groupId>com.github.wechatpay-apiv3</groupId>
            <artifactId>wechatpay-apache-httpclient</artifactId>
            <version>0.4.9</version>
        </dependency>
    </dependencies>
</project>

配置好后需要点击这个编译一下,显示成功才可继续后面的

配置git环境上传到仓库,反之代码丢失

在各自对应的结构下构建相应的目录结构

|-------------|----------------------|
| 名称 | 说明 |
| constant | 存放相关常量类 |
| context | 存放上下文类 |
| enumeration | 项目的枚举类存储 |
| exception | 存放自定义异常类 |
| json | 处理json转换的类 |
| properties | 存放SpringBoot相关的配置属性类 |
| result | 返回结果类的封装 |
| utils | 常用工具类 |

|--------|--------------------------------|
| 名称 | 说明 |
| Entity | 实体,通常和数据库中的表对应 |
| DTO | 数据传输对象,通常用于程序中各层之间传递数据 |
| VO | 视图对象,为前端展示数据提供的对象 |
| POJO | 普通Java对象,只有属性和对应的getter和setter |

|-----------------|---------------|
| 名称 | 说明 |
| config | 存放配置类 |
| controller | 存放controller类 |
| interceptor | 存放拦截器类 |
| mapper | 存放mapper接口 |
| service | 存放service类 |
| SemsApplication | 启动类 |

配置application.yml文件

sems-server/src/main/resources/application.yml

server:
  port: 8080

spring:
  profiles:
    active: dev
  main:
    allow-circular-references: true
  datasource:
    druid:
      driver-class-name: ${ljc.datasource.driver-class-name}
      url: jdbc:mysql://${ljc.datasource.host}:${ljc.datasource.port}/${ljc.datasource.database}?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf-8&zeroDateTimeBehavior=convertToNull&useSSL=false&allowPublicKeyRetrieval=true
      username: ${ljc.datasource.username}
      password: ${ljc.datasource.password}

mybatis:
  #mapper配置文件
  mapper-locations: classpath:mapper/*.xml
  type-aliases-package: com.ljc.entity
  configuration:
    #开启驼峰命名
    map-underscore-to-camel-case: true

logging:
  level:
    com:
      sky:
        mapper: debug
        service: info
        controller: info

ljc:
  jwt:
    # 设置jwt签名加密时使用的秘钥
    admin-secret-key: kussm
    # 设置jwt过期时间
    admin-ttl: 7200000
    # 设置前端传递过来的令牌名称
    admin-token-name: token

sems-server/src/main/resources/application-dev.yml

ljc:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    host: localhost
    port: 3306
    database: sems
    username: root
    password: 8888

编写一些基础代码

1. 全局异常处理器,处理项目中抛出的业务异常

GlobalExceptionHandler(全局异常处理器)

sems-server\src\main\java\com\ljc\handler\GlobalExceptionHandler.java

package com.ljc.handler;

import com.ljc.exception.BaseException;
import com.ljc.result.Result;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;

/**
 * 全局异常处理器,处理项目中抛出的业务异常
 */
@RestControllerAdvice
@Slf4j
public class GlobalExceptionHandler {

    /**
     * 捕获业务异常
     * @param ex
     * @return
     */
    @ExceptionHandler
    public Result exceptionHandler(BaseException ex){
        log.error("异常信息:{}", ex.getMessage());
        return Result.error(ex.getMessage());
    }

}

同时创建相关代码

BaseException(业务异常)

sems-common\src\main\java\com\ljc\exception\BaseException.java

package com.ljc.exception;

/**
 * 业务异常
 */
public class BaseException extends RuntimeException {

    public BaseException() {
    }

    public BaseException(String msg) {
        super(msg);
    }

}

Result(后端统一返回结果)

sems-common\src\main\java\com\ljc\result\Result.java

package com.ljc.result;

import lombok.Data;

import java.io.Serializable;

/**
 * 后端统一返回结果
 * @param <T>
 */
@Data
public class Result<T> implements Serializable {

    private Integer code; //编码:1成功,0和其它数字为失败
    private String msg; //错误信息
    private T data; //数据

    public static <T> Result<T> success() {
        Result<T> result = new Result<T>();
        result.code = 1;
        return result;
    }

    public static <T> Result<T> success(T object) {
        Result<T> result = new Result<T>();
        result.data = object;
        result.code = 1;
        return result;
    }

    public static <T> Result<T> error(String msg) {
        Result result = new Result();
        result.msg = msg;
        result.code = 0;
        return result;
    }

}

2. 配置类,注册web层相关组件JWT

注册自定义拦截器jwt

通过knife4j生成接口文档

设置静态资源映射

WebMvcConfiguration(配置类,注册web层相关组件)

sems-server\src\main\java\com\ljc\config\WebMvcConfiguration.java

package com.ljc.config;

import com.ljc.interceptor.JwtTokenAdminInterceptor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;

/**
 * 配置类,注册web层相关组件
 */
@Configuration
@Slf4j
public class WebMvcConfiguration extends WebMvcConfigurationSupport {

    @Autowired
    private JwtTokenAdminInterceptor jwtTokenAdminInterceptor;

    /**
     * 注册自定义拦截器
     *
     * @param registry
     */
    protected void addInterceptors(InterceptorRegistry registry) {
        log.info("开始注册自定义拦截器...");
        registry.addInterceptor(jwtTokenAdminInterceptor)
                .addPathPatterns("/admin/**")
                .excludePathPatterns("/admin/student/login");
    }

    /**
     * 通过knife4j生成接口文档
     * @return
     */
    @Bean
    public Docket docket() {
        ApiInfo apiInfo = new ApiInfoBuilder()
                .title("体育器材项目接口文档")
                .version("1.0")
                .description("体育器材项目接口文档")
                .build();
        Docket docket = new Docket(DocumentationType.SWAGGER_2)
                .apiInfo(apiInfo)
                .select()
                .apis(RequestHandlerSelectors.basePackage("com.ljc.controller"))
                .paths(PathSelectors.any())
                .build();
        return docket;
    }

    /**
     * 设置静态资源映射
     * @param registry
     */
    protected void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/doc.html").addResourceLocations("classpath:/META-INF/resources/");
        registry.addResourceHandler("/webjars/**").addResourceLocations("classpath:/META-INF/resources/webjars/");
    }
}

3. 相关联的jwt令牌校验的拦截器

JwtTokenAdminInterceptor

sems-server\src\main\java\com\ljc\interceptor\JwtTokenAdminInterceptor.java

package com.ljc.interceptor;

import com.ljc.constant.JwtClaimsConstant;
import com.ljc.properties.JwtProperties;
import com.ljc.utils.JwtUtil;
import io.jsonwebtoken.Claims;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * jwt令牌校验的拦截器
 */
@Component
@Slf4j
public class JwtTokenAdminInterceptor implements HandlerInterceptor {

    @Autowired
    private JwtProperties jwtProperties;

    /**
     * 校验jwt
     *
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //判断当前拦截到的是Controller的方法还是其他资源
        if (!(handler instanceof HandlerMethod)) {
            //当前拦截到的不是动态方法,直接放行
            return true;
        }

        //1、从请求头中获取令牌
        String token = request.getHeader(jwtProperties.getAdminTokenName());

        //2、校验令牌
        try {
            log.info("jwt校验:{}", token);
            Claims claims = JwtUtil.parseJWT(jwtProperties.getAdminSecretKey(), token);
            Long empId = Long.valueOf(claims.get(JwtClaimsConstant.EMP_ID).toString());
            log.info("当前员工id:", empId);
            //3、通过,放行
            return true;
        } catch (Exception ex) {
            //4、不通过,响应401状态码
            response.setStatus(401);
            return false;
        }
    }
}

4. 常量类(后面用)

JwtClaimsConstant

sems-common/src/main/java/com/ljc/constant/JwtClaimsConstant.java

package com.ljc.constant;

public class JwtClaimsConstant {

    public static final String EMP_ID = "empId";
    public static final String USER_ID = "userId";
    public static final String PHONE = "phone";
    public static final String USERNAME = "username";
    public static final String NAME = "name";

}

MessageConstant

sems-common/src/main/java/com/ljc/constant/MessageConstant.java

package com.ljc.constant;

/**
 * 信息提示常量类
 */
public class MessageConstant {

    public static final String PASSWORD_ERROR = "密码错误";
    public static final String ACCOUNT_NOT_FOUND = "账号不存在";
    public static final String ACCOUNT_LOCKED = "账号被锁定";
    public static final String UNKNOWN_ERROR = "未知错误";
    public static final String USER_NOT_LOGIN = "用户未登录";
    public static final String CATEGORY_BE_RELATED_BY_SETMEAL = "当前分类关联了套餐,不能删除";
    public static final String CATEGORY_BE_RELATED_BY_DISH = "当前分类关联了菜品,不能删除";
    public static final String SHOPPING_CART_IS_NULL = "购物车数据为空,不能下单";
    public static final String ADDRESS_BOOK_IS_NULL = "用户地址为空,不能下单";
    public static final String LOGIN_FAILED = "登录失败";
    public static final String UPLOAD_FAILED = "文件上传失败";
    public static final String SETMEAL_ENABLE_FAILED = "套餐内包含未启售菜品,无法启售";
    public static final String PASSWORD_EDIT_FAILED = "密码修改失败";
    public static final String DISH_ON_SALE = "起售中的菜品不能删除";
    public static final String SETMEAL_ON_SALE = "起售中的套餐不能删除";
    public static final String DISH_BE_RELATED_BY_SETMEAL = "当前菜品关联了套餐,不能删除";
    public static final String ORDER_STATUS_ERROR = "订单状态错误";
    public static final String ORDER_NOT_FOUND = "订单不存在";

}

StatusConstant

sems-common/src/main/java/com/ljc/constant/StatusConstant.java

package com.ljc.constant;

/**
 * 状态常量,启用或者禁用
 */
public class StatusConstant {

    //启用
    public static final Integer ENABLE = 1;

    //禁用
    public static final Integer DISABLE = 0;
}

5. 异常类

AccountLockedException

sems-common/src/main/java/com/ljc/exception/AccountLockedException.java

package com.ljc.exception;

/**
 * 账号被锁定异常
 */
public class AccountLockedException extends BaseException {

    public AccountLockedException() {
    }

    public AccountLockedException(String msg) {
        super(msg);
    }

}

AccountNotFoundException

sems-common/src/main/java/com/ljc/exception/AccountNotFoundException.java

package com.ljc.exception;

/**
 * 账号不存在异常
 */
public class AccountNotFoundException extends BaseException {

    public AccountNotFoundException() {
    }

    public AccountNotFoundException(String msg) {
        super(msg);
    }

}

PasswordErrorException

sems-common/src/main/java/com/ljc/exception/PasswordErrorException.java

package com.ljc.exception;

/**
 * 密码错误异常
 */
public class PasswordErrorException extends BaseException {

    public PasswordErrorException() {
    }

    public PasswordErrorException(String msg) {
        super(msg);
    }

}

6. 配置类

JwtProperties

sems-common/src/main/java/com/ljc/properties/JwtProperties.java

package com.ljc.properties;

import lombok.Data;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

@Component
@ConfigurationProperties(prefix = "ljc.jwt")
@Data
public class JwtProperties {

    /**
     * 管理端员工生成jwt令牌相关配置
     */
    private String adminSecretKey;
    private long adminTtl;
    private String adminTokenName;

    /**
     * 用户端微信用户生成jwt令牌相关配置
     */
    private String userSecretKey;
    private long userTtl;
    private String userTokenName;

}

7. 实用工具

JwtUtil(生成jwt)

sems-common/src/main/java/com/ljc/utils/JwtUtil.java

package com.ljc.utils;

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.JwtBuilder;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;

import java.nio.charset.StandardCharsets;
import java.util.Date;
import java.util.Map;

public class JwtUtil {
    /**
     * 生成jwt
     * 使用Hs256算法, 私匙使用固定秘钥
     *
     * @param secretKey jwt秘钥
     * @param ttlMillis jwt过期时间(毫秒)
     * @param claims    设置的信息
     * @return
     */
    public static String createJWT(String secretKey, long ttlMillis, Map<String, Object> claims) {
        // 指定签名的时候使用的签名算法,也就是header那部分
        SignatureAlgorithm signatureAlgorithm = SignatureAlgorithm.HS256;

        // 生成JWT的时间
        long expMillis = System.currentTimeMillis() + ttlMillis;
        Date exp = new Date(expMillis);

        // 设置jwt的body
        JwtBuilder builder = Jwts.builder()
                // 如果有私有声明,一定要先设置这个自己创建的私有的声明,这个是给builder的claim赋值,一旦写在标准的声明赋值之后,就是覆盖了那些标准的声明的
                .setClaims(claims)
                // 设置签名使用的签名算法和签名使用的秘钥
                .signWith(signatureAlgorithm, secretKey.getBytes(StandardCharsets.UTF_8))
                // 设置过期时间
                .setExpiration(exp);

        return builder.compact();
    }

    /**
     * Token解密
     *
     * @param secretKey jwt秘钥 此秘钥一定要保留好在服务端, 不能暴露出去, 否则sign就可以被伪造, 如果对接多个客户端建议改造成多个
     * @param token     加密后的token
     * @return
     */
    public static Claims parseJWT(String secretKey, String token) {
        // 得到DefaultJwtParser
        Claims claims = Jwts.parser()
                // 设置签名的秘钥
                .setSigningKey(secretKey.getBytes(StandardCharsets.UTF_8))
                // 设置需要解析的jwt
                .parseClaimsJws(token).getBody();
        return claims;
    }

}

8. 阶段效果展示

现在就可以开始运行代码了

SemsApplication

sems-server/src/main/java/com/ljc/SemsApplication.java

package com.ljc;

import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.transaction.annotation.EnableTransactionManagement;

@SpringBootApplication
@EnableTransactionManagement //开启注解方式的事务管理
@Slf4j
public class SemsApplication {
    public static void main(String[] args) {
        SpringApplication.run(SemsApplication.class, args);
        log.info("server started");
    }
}

打开浏览器输入:http://localhost:8080/doc.html

可以看到通过knife4j生成的初步接口文档,后面慢慢完善接口

学生管理--登录

接口设计

请求路径:/admin/student/login

请求方式:POST

设计数据库

student表为学生表,用于存储学生信息。具体表结构如下:

|-------------|-------------|---------|---------|
| 字段名 | 数据类型 | 说明 | 备注 |
| id | bigint | 主键 | 自增 |
| name | varchar(32) | 姓名 | |
| username | varchar(32) | 用户名 | 唯一 |
| password | varchar(64) | 密码 | |
| phone | varchar(11) | 手机号 | |
| sex | varchar(2) | 性别 | |
| id_number | varchar(18) | 身份证号 | |
| status | int | 账号状态 | 1正常 0锁定 |
| create_time | datetime | 创建时间 | |
| update_time | datetime | 最后修改时间 | |
| create_user | bigint | 创建人id | |
| update_user | bigint | 最后修改人id | |

sql语句

DROP TABLE IF EXISTS student;
CREATE TABLE `employee` (
    `id` bigint NOT NULL AUTO_INCREMENT COMMENT '主键',
    `name` varchar(32) COLLATE utf8_bin NOT NULL COMMENT '姓名',
    `username` varchar(32) COLLATE utf8_bin NOT NULL COMMENT '用户名',
    `password` varchar(64) COLLATE utf8_bin NOT NULL COMMENT '密码',
    `phone` varchar(11) COLLATE utf8_bin NOT NULL COMMENT '手机号',
    `sex` varchar(2) COLLATE utf8_bin NOT NULL COMMENT '性别',
    `id_number` varchar(18) COLLATE utf8_bin NOT NULL COMMENT '身份证号',
    `status` int NOT NULL DEFAULT '1' COMMENT '状态 0:禁用,1:启用',
    `create_time` datetime DEFAULT NULL COMMENT '创建时间',
    `update_time` datetime DEFAULT NULL COMMENT '更新时间',
    `create_user` bigint DEFAULT NULL COMMENT '创建人',
    `update_user` bigint DEFAULT NULL COMMENT '修改人',
    PRIMARY KEY (`id`),
    UNIQUE KEY `idx_username` (`username`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8mb3 COLLATE=utf8_bin COMMENT='员工信息';

INSERT INTO student VALUES (1,'管理员','admin','123456','13812312312','1','110101199001010047',1,'2022-02-15 15:51:20','2022-02-17 09:16:20',10,1);

设计接收和回传数据的DTO和VO结构以及和数据库对应的entity实体类

Student

sems-pojo/src/main/java/com/ljc/entity/Student.java

package com.ljc.entity;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.io.Serializable;
import java.time.LocalDateTime;

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class Student implements Serializable {
    private static final long serialVersionUID = 1L;

    private Long id;

    private String username;

    private String name;

    private String password;

    private String phone;

    private String sex;

    private String idNumber;

    private Integer status;

    //@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private LocalDateTime createTime;

    //@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private LocalDateTime updateTime;

    private Long createUser;

    private Long updateUser;

}

StudentLoginDTO

sems-pojo/src/main/java/com/ljc/dto/StudentLoginDTO.java

package com.ljc.dto;

import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;

import java.io.Serializable;

@Data
@ApiModel(description = "学生登录时传递的数据模型")
public class StudentLoginDTO implements Serializable {

    @ApiModelProperty("用户名")
    private String username;

    @ApiModelProperty("密码")
    private String password;
}

StudentLoginVO

sems-pojo/src/main/java/com/ljc/vo/StudentLoginVO.java

package com.ljc.vo;

import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.io.Serializable;

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
@ApiModel(description = "学生登录返回的数据格式")
public class StudentLoginVO implements Serializable {
    @ApiModelProperty("主键值")
    private Long id;

    @ApiModelProperty("用户名")
    private String userName;

    @ApiModelProperty("姓名")
    private String name;

    @ApiModelProperty("jwt令牌")
    private String token;

}

设计真正业务的代码

controller层-StudentController

sems-server/src/main/java/com/ljc/controller/student/StudentController.java

package com.ljc.controller.student;

import com.ljc.constant.JwtClaimsConstant;
import com.ljc.dto.StudentLoginDTO;
import com.ljc.entity.Student;
import com.ljc.properties.JwtProperties;
import com.ljc.result.Result;
import com.ljc.service.StudentService;
import com.ljc.utils.JwtUtil;
import com.ljc.vo.StudentLoginVO;

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.HashMap;
import java.util.Map;

@RestController
@RequestMapping("/admin/student")
@Slf4j
public class StudentController {
    @Autowired
    private StudentService studentService;
    @Autowired
    private JwtProperties jwtProperties;

    /**
     * 登录
     *
     * @param studentLoginDTO
     * @return
     */
    @PostMapping("/login")
    public Result<StudentLoginVO> login(@RequestBody StudentLoginDTO studentLoginDTO) {
        log.info("学生登录:{}", studentLoginDTO);

        Student student = studentService.login(studentLoginDTO);

        //登录成功后,生成jwt令牌
        Map<String, Object> claims = new HashMap<>();
        claims.put(JwtClaimsConstant.EMP_ID, student.getId());
        String token = JwtUtil.createJWT(
                jwtProperties.getAdminSecretKey(),
                jwtProperties.getAdminTtl(),
                claims);

        StudentLoginVO studentLoginVO = StudentLoginVO.builder()
                .id(student.getId())
                .userName(student.getUsername())
                .name(student.getName())
                .token(token)
                .build();

        return Result.success(studentLoginVO);
    }

    /**
     * 退出
     *
     * @return
     */
    @PostMapping("/logout")
    public Result<String> logout() {
        return Result.success();
    }
}

service层-StudentService

sems-server/src/main/java/com/ljc/service/StudentService.java

package com.ljc.service;

import com.ljc.dto.StudentLoginDTO;
import com.ljc.entity.Student;

public interface StudentService {

    /**
     * 学生登录
     * @param studentLoginDTO
     * @return
     */
    Student login(StudentLoginDTO studentLoginDTO);

}

service层-StudentServiceImpl

sems-server/src/main/java/com/ljc/service/impl/StudentServiceImpl.java

package com.ljc.service.impl;

import com.ljc.constant.MessageConstant;
import com.ljc.constant.StatusConstant;
import com.ljc.dto.StudentLoginDTO;
import com.ljc.entity.Student;
import com.ljc.exception.AccountLockedException;
import com.ljc.exception.AccountNotFoundException;
import com.ljc.exception.PasswordErrorException;
import com.ljc.mapper.StudentMapper;
import com.ljc.service.StudentService;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class StudentServiceImpl implements StudentService {

    @Autowired
    private StudentMapper studentMapper;

    /**
     * 学生登录
     *
     * @param studentLoginDTO
     * @return
     */
    public Student login(StudentLoginDTO studentLoginDTO) {
        String username = studentLoginDTO.getUsername();
        String password = studentLoginDTO.getPassword();

        //1、根据用户名查询数据库中的数据
        Student student = studentMapper.getByUsername(username);

        //2、处理各种异常情况(用户名不存在、密码不对、账号被锁定)
        if (student == null) {
            //账号不存在
            throw new AccountNotFoundException(MessageConstant.ACCOUNT_NOT_FOUND);
        }

        //密码比对
        // TODO 后期需要进行md5加密,然后再进行比对
        if (!password.equals(student.getPassword())) {
            //密码错误
            throw new PasswordErrorException(MessageConstant.PASSWORD_ERROR);
        }

        if (student.getStatus() == StatusConstant.DISABLE) {
            //账号被锁定
            throw new AccountLockedException(MessageConstant.ACCOUNT_LOCKED);
        }

        //3、返回实体对象
        return student;
    }

}

mapper层-StudentMapper

sems-server/src/main/java/com/ljc/mapper/StudentMapper.java

package com.ljc.mapper;

import com.ljc.entity.Student;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

@Mapper
public interface StudentMapper {

    /**
     * 根据用户名查询学生
     * @param username
     * @return
     */
    @Select("select * from student where username = #{username}")
    Student getByUsername(String username);

}

阶段结果展示

通过swagger测试

注意:我在运行中出现的一些问题:

基本就没什么问题了。

这样登录功能就搞定了!!!!!

目前为止整体结构

完善登录功能

学生表中的密码是明文存储,安全性太低

使用MD5加密方式对明文密码加密

"123456"进行MD5加密后结果为:

e10adc3949ba59abbe56e057f20f883e

进入数据库,修改密码为这个

修改代码

完整代码:

sems-server/src/main/java/com/ljc/service/impl/StudentServiceImpl.java

package com.ljc.service.impl;

import com.ljc.constant.MessageConstant;
import com.ljc.constant.StatusConstant;
import com.ljc.dto.StudentLoginDTO;
import com.ljc.entity.Student;
import com.ljc.exception.AccountLockedException;
import com.ljc.exception.AccountNotFoundException;
import com.ljc.exception.PasswordErrorException;
import com.ljc.mapper.StudentMapper;
import com.ljc.service.StudentService;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.DigestUtils;

@Service
public class StudentServiceImpl implements StudentService {

    @Autowired
    private StudentMapper studentMapper;

    /**
     * 学生登录
     *
     * @param studentLoginDTO
     * @return
     */
    public Student login(StudentLoginDTO studentLoginDTO) {
        String username = studentLoginDTO.getUsername();
        String password = studentLoginDTO.getPassword();

        //1、根据用户名查询数据库中的数据
        Student student = studentMapper.getByUsername(username);

        //2、处理各种异常情况(用户名不存在、密码不对、账号被锁定)
        if (student == null) {
            //账号不存在
            throw new AccountNotFoundException(MessageConstant.ACCOUNT_NOT_FOUND);
        }

        //密码比对
        // 进行md5加密,然后再进行比对
        password = DigestUtils.md5DigestAsHex(password.getBytes());
        if (!password.equals(student.getPassword())) {
            //密码错误
            throw new PasswordErrorException(MessageConstant.PASSWORD_ERROR);
        }

        if (student.getStatus() == StatusConstant.DISABLE) {
            //账号被锁定
            throw new AccountLockedException(MessageConstant.ACCOUNT_LOCKED);
        }

        //3、返回实体对象
        return student;
    }

}

初步完成这样

相关推荐
LXMXHJ7 分钟前
Java-Redis-Clickhouse-Jenkins-MybatisPlus-Zookeeper-vscode-Docker
java·redis·java-zookeeper
又该洗头了11 分钟前
Swagger
java·spring·swagger
bingbingyihao22 分钟前
Linux安装ftp、Java的FTP上传下载文件工具类
java·linux·centos
u01040583629 分钟前
如何利用Java Stream API简化集合操作?
java·开发语言
G皮T31 分钟前
【MyBatis】MyBatis 理论 40 问(二)
java·数据库·spring boot·spring·mybatis·关系映射
小羊子说40 分钟前
Android 开发中 C++ 和Java 日志调试
android·java·c++
TechQuester44 分钟前
解决GPT-4o耗电难题!DeepMind新算法训练效率提升13倍,能耗降低10倍!
java·c++·人工智能·python·算法·chatgpt
球球King1 小时前
工厂模式之简单工厂模式
java·jvm·简单工厂模式
续亮~1 小时前
6、Redis系统-数据结构-06-跳表
java·数据结构·数据库·redis·后端·缓存
码界领航1 小时前
【Spring Cloud】一个例程快速了解网关Gateway的使用
spring·spring cloud·gateway